A. Field of the Invention
The present invention relates generally to system cooling and, more particularly, to directing airflow in three dimensions to cool components of a system, especially electronic components mounted on circuit boards in a system.
B. Description of Related Art
Conventional electronic systems, such as a large-scale computers and networking devices, often contain circuit boards on which electronic components are mounted. During operation, the electronic components in these systems dissipate heat, causing the internal system temperature to rise. The amount of temperature rise depends on various factors, such as the number, types, and complexity of the components. To avoid reaching internal temperatures that may adversely affect system operation or performance, many systems are equipped with cooling mechanisms.
One type of cooling mechanism involves forcing air through a system to cool its components. For example, fans may be positioned to draw outside air into the system through an air inlet, blow the air along the surface of circuit boards, and expel the heated air out of the system. The positioning of these fans is influenced by the arrangement and/or alignment of (1) the components on the boards and (2) the boards in the system.
This type of cooling mechanism, however, suffers several drawbacks. First, the effectiveness of the cooling mechanism may be affected by the location of the air inlet. In some cases, the air around the air inlet may be heated. This may happen, for example, where the air inlet of one system is located close to the air outlet of another system. It is common (especially with networking devices and large computer systems) for two or more systems with cooling mechanisms to be located side-by-side in close proximity. In these cases, the cooling mechanism draws in heated air expelled from the adjacent system, which prevents effective cooling of the electronic components.
Another drawback with forced-air cooling mechanisms is that the amount of cooling may vary in different areas of a system. Areas exposed to higher airflow velocity typically cool faster than areas exposed to lower airflow velocity. This may be problematic in areas in which the airflow velocity is too low to provide sufficient cooling to the affected components. Airflow velocity changes and variations are apt to occur in complex systems, in which the airflow direction may change one or more times and/or in which a single airflow source feeds into multiple airflow branches for cooling respective circuit boards.
Therefore, there is a need for a cooling mechanism for electronic systems that solves the problems and overcomes the drawbacks of prior art cooling mechanisms.
Systems and methods, consistent with the present invention, address this and other needs by providing forced-air cooling to components mounted on circuit boards oriented in a side-to-side direction in a system. Airflow may enter and exit the system through the front and back (or vice-versa), rather than the sides of the system. In one embodiment, airflow entering the front of the system is re-directed in an upward direction, then split to form airflow branches traversing in a side-to-side direction. The airflow branches traverse across the surfaces of circuit boards, then are directed in an upward direction and out the back (or front) of the system. The airflow branches preferably move substantially the same volume of air per unit of time.
In accordance with the purpose of the invention as embodied and broadly described herein, a cooling mechanism comprises an air inlet for drawing airflow in a front-to-back direction, an exhaust module for drawing airflow from the air-intake module to an upward direction; at least one air guide for redirecting airflow from the first module to a plurality of airflow branches in a side-to-side direction; a vertical pathway for combining the plurality of airflow branches to form an airflow in the upward direction; and a second exhaust module for redirecting airflow, to the front-to-back direction, from the vertical pathway and expelling the airflow out of the system.
Other implementations and concepts consistent with the invention are described. The invention is defined by the claims.